Refactor VM to own its context

This commit is contained in:
Jeff 2024-08-12 08:54:21 -04:00
parent bf11bd1f0f
commit c71c4d2d07
4 changed files with 119 additions and 112 deletions

View File

@ -1,10 +1,9 @@
//! Tools for analyzing an abstract syntax tree and catch errors before running the virtual
//! machine.
//!
//! This module provides to anlysis options, both of which borrow an abstract syntax tree and a
//! hash map of variables:
//! - `analyze` convenience function
//! - `Analyzer` struct
//! This module provides two anlysis options:
//! - `analyze` convenience function, which takes a string input
//! - `Analyzer` struct, which borrows an abstract syntax tree and a context
use std::{
error::Error,
fmt::{self, Display, Formatter},
@ -28,8 +27,8 @@ use crate::{
/// ```
pub fn analyze(source: &str) -> Result<(), DustError> {
let abstract_tree = parse(source)?;
let mut context = Context::new();
let mut analyzer = Analyzer::new(&abstract_tree, &mut context);
let context = Context::new();
let mut analyzer = Analyzer::new(&abstract_tree, &context);
analyzer
.analyze()
@ -54,11 +53,11 @@ pub fn analyze(source: &str) -> Result<(), DustError> {
/// assert!(result.is_err());
pub struct Analyzer<'a> {
abstract_tree: &'a AbstractSyntaxTree,
context: &'a mut Context,
context: &'a Context,
}
impl<'a> Analyzer<'a> {
pub fn new(abstract_tree: &'a AbstractSyntaxTree, context: &'a mut Context) -> Self {
pub fn new(abstract_tree: &'a AbstractSyntaxTree, context: &'a Context) -> Self {
Self {
abstract_tree,
context,

View File

@ -21,6 +21,15 @@ impl Context {
}
}
pub fn with_variables_from(other: &Self) -> Self {
Self {
variables: Arc::new(RwLock::new(other.variables.read().unwrap().clone())),
is_garbage_collected_to: Arc::new(RwLock::new(
*other.is_garbage_collected_to.read().unwrap(),
)),
}
}
pub fn variable_count(&self) -> usize {
self.variables.read().unwrap().len()
}
@ -54,7 +63,7 @@ impl Context {
}
}
pub fn set_type(&mut self, identifier: Identifier, r#type: Type, position: Span) {
pub fn set_type(&self, identifier: Identifier, r#type: Type, position: Span) {
log::trace!("Setting {identifier} to type {type} at {position:?}");
self.variables
@ -63,7 +72,7 @@ impl Context {
.insert(identifier, (VariableData::Type(r#type), position));
}
pub fn set_value(&mut self, identifier: Identifier, value: Value) {
pub fn set_value(&self, identifier: Identifier, value: Value) {
log::trace!("Setting {identifier} to value {value}");
let mut variables = self.variables.write().unwrap();
@ -76,7 +85,7 @@ impl Context {
variables.insert(identifier, (VariableData::Value(value), last_position));
}
pub fn collect_garbage(&mut self, current_position: usize) {
pub fn collect_garbage(&self, current_position: usize) {
log::trace!("Collecting garbage up to {current_position}");
let mut is_garbage_collected_to = self.is_garbage_collected_to.write().unwrap();
@ -101,7 +110,7 @@ impl Context {
*is_garbage_collected_to = current_position;
}
pub fn update_last_position(&mut self, identifier: &Identifier, position: Span) -> bool {
pub fn update_last_position(&self, identifier: &Identifier, position: Span) -> bool {
if let Some((_, last_position)) = self.variables.write().unwrap().get_mut(identifier) {
*last_position = position;
@ -142,9 +151,9 @@ mod tests {
z = x + y
z
";
let mut context = Context::new();
let context = Context::new();
run_with_context(source, &mut context).unwrap();
run_with_context(source, context.clone()).unwrap();
assert_eq!(context.variable_count(), 0);
}
@ -158,9 +167,9 @@ mod tests {
z = z + y
}
";
let mut context = Context::new();
let context = Context::new();
run_with_context(source, &mut context).unwrap();
run_with_context(source, context.clone()).unwrap();
assert_eq!(context.variable_count(), 0);
}

View File

@ -748,9 +748,9 @@ impl Function {
self,
_type_arguments: Option<Vec<Type>>,
value_arguments: Option<Vec<Value>>,
context: &mut Context,
context: &Context,
) -> Result<Option<Value>, VmError> {
let mut new_context = context.clone();
let new_context = Context::with_variables_from(context);
if let (Some(value_parameters), Some(value_arguments)) =
(self.value_parameters, value_arguments)
@ -760,9 +760,9 @@ impl Function {
}
}
let mut vm = Vm::new(self.body);
let mut vm = Vm::new(self.body, new_context);
vm.run(&mut new_context)
vm.run()
}
pub fn return_type(&self, variables: &Context) -> Option<Type> {

View File

@ -1,27 +1,29 @@
//! Virtual machine for running the abstract syntax tree.
//!
//! This module provides three running option:
//! - `run` convenience function that takes a source code string and runs it
//! - `run_with_context` convenience function that takes a source code string and a context
//! - `Vm` struct that can be used to run an abstract syntax tree
use std::{
collections::BTreeMap,
fmt::{self, Display, Formatter},
};
use crate::{
abstract_tree::BinaryOperator, parse, value::ValueInner, AbstractSyntaxTree, Analyzer,
BuiltInFunctionError, Context, DustError, Identifier, Node, ParseError, Span, Statement,
UnaryOperator, Value, ValueError,
parse, value::ValueInner, AbstractSyntaxTree, Analyzer, BinaryOperator, BuiltInFunctionError,
Context, DustError, Identifier, Node, ParseError, Span, Statement, UnaryOperator, Value,
ValueError,
};
pub fn run(source: &str) -> Result<Option<Value>, DustError> {
let mut context = Context::new();
let context = Context::new();
run_with_context(source, &mut context)
run_with_context(source, context)
}
pub fn run_with_context<'src>(
source: &'src str,
context: &mut Context,
) -> Result<Option<Value>, DustError<'src>> {
pub fn run_with_context(source: &str, context: Context) -> Result<Option<Value>, DustError> {
let abstract_syntax_tree = parse(source)?;
let mut analyzer = Analyzer::new(&abstract_syntax_tree, context);
let mut analyzer = Analyzer::new(&abstract_syntax_tree, &context);
analyzer
.analyze()
@ -30,45 +32,45 @@ pub fn run_with_context<'src>(
source,
})?;
let mut vm = Vm::new(abstract_syntax_tree);
let mut vm = Vm::new(abstract_syntax_tree, context);
vm.run(context)
vm.run()
.map_err(|vm_error| DustError::VmError { vm_error, source })
}
pub struct Vm {
abstract_tree: AbstractSyntaxTree,
context: Context,
}
impl Vm {
pub fn new(abstract_tree: AbstractSyntaxTree) -> Self {
Self { abstract_tree }
pub fn new(abstract_tree: AbstractSyntaxTree, context: Context) -> Self {
Self {
abstract_tree,
context,
}
}
pub fn run(&mut self, context: &mut Context) -> Result<Option<Value>, VmError> {
pub fn run(&mut self) -> Result<Option<Value>, VmError> {
let mut previous_position = (0, 0);
let mut previous_value = None;
while let Some(statement) = self.abstract_tree.nodes.pop_front() {
let new_position = statement.position;
previous_value = self.run_statement(statement, context)?;
previous_value = self.run_statement(statement)?;
context.collect_garbage(previous_position.1);
self.context.collect_garbage(previous_position.1);
previous_position = new_position;
}
context.collect_garbage(previous_position.1);
self.context.collect_garbage(previous_position.1);
Ok(previous_value)
}
fn run_statement(
&self,
node: Node<Statement>,
context: &mut Context,
) -> Result<Option<Value>, VmError> {
fn run_statement(&self, node: Node<Statement>) -> Result<Option<Value>, VmError> {
match node.inner {
Statement::BinaryOperation {
left,
@ -85,7 +87,7 @@ impl Vm {
position: left.position,
});
};
let value = if let Some(value) = self.run_statement(*right, context)? {
let value = if let Some(value) = self.run_statement(*right)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -93,7 +95,7 @@ impl Vm {
});
};
context.set_value(identifier, value);
self.context.set_value(identifier, value);
return Ok(None);
}
@ -101,7 +103,7 @@ impl Vm {
if let BinaryOperator::AddAssign = operator.inner {
let (identifier, left_value) =
if let Statement::Identifier(identifier) = left.inner {
let value = context.get_value(&identifier).ok_or_else(|| {
let value = self.context.get_value(&identifier).ok_or_else(|| {
VmError::UndefinedVariable {
identifier: Node::new(
Statement::Identifier(identifier.clone()),
@ -116,7 +118,7 @@ impl Vm {
position: left.position,
});
};
let right_value = if let Some(value) = self.run_statement(*right, context)? {
let right_value = if let Some(value) = self.run_statement(*right)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -130,20 +132,20 @@ impl Vm {
}
})?;
context.set_value(identifier, new_value);
self.context.set_value(identifier, new_value);
return Ok(None);
}
let left_position = left.position;
let left_value = if let Some(value) = self.run_statement(*left, context)? {
let left_value = if let Some(value) = self.run_statement(*left)? {
value
} else {
return Err(VmError::ExpectedValue {
position: left_position,
});
};
let right_value = if let Some(value) = self.run_statement(*right, context)? {
let right_value = if let Some(value) = self.run_statement(*right)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -178,7 +180,7 @@ impl Vm {
let mut previous_value = None;
for statement in statements {
previous_value = self.run_statement(statement, context)?;
previous_value = self.run_statement(statement)?;
}
Ok(previous_value)
@ -193,7 +195,7 @@ impl Vm {
for node in nodes {
let position = node.position;
let value = if let Some(value) = self.run_statement(node, context)? {
let value = if let Some(value) = self.run_statement(node)? {
value
} else {
return Err(VmError::ExpectedValue { position });
@ -223,8 +225,7 @@ impl Vm {
value_arguments: value_parameter_nodes,
} => {
let function_position = function_node.position;
let function_value =
if let Some(value) = self.run_statement(*function_node, context)? {
let function_value = if let Some(value) = self.run_statement(*function_node)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -245,7 +246,7 @@ impl Vm {
for node in value_nodes {
let position = node.position;
let value = if let Some(value) = self.run_statement(node, context)? {
let value = if let Some(value) = self.run_statement(node)? {
value
} else {
return Err(VmError::ExpectedValue { position });
@ -259,10 +260,12 @@ impl Vm {
None
};
Ok(function.clone().call(None, value_parameters, context)?)
Ok(function
.clone()
.call(None, value_parameters, &self.context)?)
}
Statement::Identifier(identifier) => {
let value_option = context.get_value(&identifier);
let value_option = self.context.get_value(&identifier);
if let Some(value) = value_option {
Ok(Some(value.clone()))
@ -274,8 +277,7 @@ impl Vm {
}
Statement::If { condition, body } => {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(*condition, context)? {
let condition_value = if let Some(value) = self.run_statement(*condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -291,7 +293,7 @@ impl Vm {
};
if condition {
self.run_statement(*body, context)?;
self.run_statement(*body)?;
}
Ok(None)
@ -302,8 +304,7 @@ impl Vm {
else_body,
} => {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(*condition, context)? {
let condition_value = if let Some(value) = self.run_statement(*condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -313,9 +314,9 @@ impl Vm {
if let Some(condition) = condition_value.as_boolean() {
if condition {
self.run_statement(*if_body, context)
self.run_statement(*if_body)
} else {
self.run_statement(*else_body, context)
self.run_statement(*else_body)
}
} else {
Err(VmError::ExpectedBoolean {
@ -329,8 +330,7 @@ impl Vm {
else_ifs,
} => {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(*condition, context)? {
let condition_value = if let Some(value) = self.run_statement(*condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -340,12 +340,12 @@ impl Vm {
if let Some(condition) = condition_value.as_boolean() {
if condition {
self.run_statement(*if_body, context)
self.run_statement(*if_body)
} else {
for (condition, body) in else_ifs {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(condition, context)? {
if let Some(value) = self.run_statement(condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -361,7 +361,7 @@ impl Vm {
};
if condition {
self.run_statement(body, context)?;
self.run_statement(body)?;
}
}
@ -380,8 +380,7 @@ impl Vm {
else_body,
} => {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(*condition, context)? {
let condition_value = if let Some(value) = self.run_statement(*condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -391,12 +390,12 @@ impl Vm {
if let Some(condition) = condition_value.as_boolean() {
if condition {
self.run_statement(*if_body, context)
self.run_statement(*if_body)
} else {
for (condition, body) in else_ifs {
let condition_position = condition.position;
let condition_value =
if let Some(value) = self.run_statement(condition, context)? {
if let Some(value) = self.run_statement(condition)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -412,11 +411,11 @@ impl Vm {
};
if condition {
return self.run_statement(body, context);
return self.run_statement(body);
}
}
self.run_statement(*else_body, context)
self.run_statement(*else_body)
}
} else {
Err(VmError::ExpectedBoolean {
@ -429,7 +428,7 @@ impl Vm {
.into_iter()
.map(|node| {
let span = node.position;
if let Some(value) = self.run_statement(node, context)? {
if let Some(value) = self.run_statement(node)? {
Ok(value)
} else {
Err(VmError::ExpectedValue { position: span })
@ -451,7 +450,7 @@ impl Vm {
});
};
let position = value_node.position;
let value = if let Some(value) = self.run_statement(value_node, context)? {
let value = if let Some(value) = self.run_statement(value_node)? {
value
} else {
return Err(VmError::ExpectedValue { position });
@ -463,13 +462,13 @@ impl Vm {
Ok(Some(Value::map(values)))
}
Statement::Nil(node) => {
let _return = self.run_statement(*node, context)?;
let _return = self.run_statement(*node)?;
Ok(None)
}
Statement::PropertyAccess(left, right) => {
let left_span = left.position;
let left_value = if let Some(value) = self.run_statement(*left, context)? {
let left_value = if let Some(value) = self.run_statement(*left)? {
value
} else {
return Err(VmError::ExpectedValue {
@ -502,7 +501,7 @@ impl Vm {
}
Statement::UnaryOperation { operator, operand } => {
let position = operand.position;
let value = if let Some(value) = self.run_statement(*operand, context)? {
let value = if let Some(value) = self.run_statement(*operand)? {
value
} else {
return Err(VmError::ExpectedValue { position });
@ -532,7 +531,7 @@ impl Vm {
let condition_position = condition.position;
while let Some(condition_value) = self.run_statement(*condition.clone(), context)? {
while let Some(condition_value) = self.run_statement(*condition.clone())? {
if let ValueInner::Boolean(condition_value) = condition_value.inner().as_ref() {
if !condition_value {
break;
@ -543,7 +542,7 @@ impl Vm {
});
}
return_value = self.run_statement(*body.clone(), context)?;
return_value = self.run_statement(*body.clone())?;
if return_value.is_some() {
break;